Generational Replacement
Because people's formative experiences in pre-adult years tend to shape them throughout later life, if the younger birth cohorts in a given society have experienced fundamentally different conditions than those that shaped older birth cohorts, one will find substantial and persisting differences between the basic values of older and younger generations. As the younger birth cohorts gradually replace the older ones over time, one will observe predictable changes in the values and behavior of the population of that society as a whole.
People concerned with 'maintaining order' and 'fighting rising prices' are classified as Materialists, while those who choose 'giving the people more say' and 'freedom of speech' are classified as expressing Postmaterialism.[1]
The main case of generational replacement in Abramson and Ronald Inglehart’s article, was the shift from Materialist to Postmaterialist values among the publics of advanced industrial societies. This shift reflected the fact that the post-war birth cohorts of Western societies had experienced unprecedented prosperity, the post-war welfare states and the absence of war that prevailed after 1945—while the older cohorts had been shaped by the economic and physical insecurity linked with World War I, the Great Depression and World War II.